in gaithersburg, maryland, about 20 miles north we have of the nation's capitol. the quake was felt by as many as 3 million people in the mid-atlantic region. there were no reports of injuries or damage, but residents flooded 911 lines to report the rumbling. let's get more now from someone who actually felt it. cnn producer trish chicka, who was at home in kensington, maryland, when the quake hit and joins us right now on the phone. what did you feel and hear? >> caller: hi, fredricka. i had just gotten out of the shower at the time, and all of a sudden i felt you know, my -- the bottom of the tub was vibrating. the low, deep rumble. the windows, or the window flight my shower, it was rattling. it felt like a train or a huge truck was going by, but, of course, i would have had to been right outside my window if that were the case. it didn't make any sense, and i felt this momentary, maybe low level feeling of panic. i'm in the shower. i'm thinking, that's kind of a vulnerable place to be. should i -- >> were you thinking, this is a tremor? an earthquake? or thinking something else was going o